Device for dispensing a gas-liquid mixture

ABSTRACT

A device is provided for dispensing a gas-liquid mixture which comprises a horizontal header with a plurality of inlet pipe connections for a gas-liquid mixture, the header having open discharge pipes connected thereto at the top thereof and containing vertical tubes within the header and provided with holes extending over the entire length of the tubes. The upper end of each tube extends into and in communication with a respective discharge pipe and the lower end is open. Preferably, the lower ends of the tubes are provided with teeth whose tips rest on the inner wall of the header.

United States Patent [72] Inventors Ivan Ivanovich Koshelev [56] References Cited Novye Cheremushki. Kvartal 30, Korp. 49, UNITED STATES PATENTS Kv. 52'

1,988,659 l/l935 LaMont l22/406X Rummy 2,907,306 10/1959 Stabenow 122/406 Pryanishnikova, 88, kv. 9, Moscow,

U.S.S.R. 21 AppLNo. 757,811 221 Filed Sept. 6. 1968 [45] Patented Feb. 2, 1971 [54] DEVICE FOR DISPENSING A GAS-LIQUID Primary ExaminerKenneth W. Sprague Attorney-Waters, Roditi, Schwartz & Nissen ABSTRACT: A device is provided for dispensing a gas-liquid mixture which comprises a horizontal header with a plurality of inletpipe connections for a gas-liquid mixture, the header having open discharge pipes connected thereto at the top Drawin 5 thereof and containing vertical tubes within the header and g lg provided with holes extending over the entire length of the [52] US. Cl 122/406 tubes The upper end of each tube extends into and in commu- [51] Int. Cl F22d 7/00 nication with a respective discharge pipe and the lower end is [50] Field of Search 122/406, open. Preferably, the lower ends of the tubes are provided 406R, 407 with teeth whose tips rest on the inner wall of the header.

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DEVICE FOR DISPENSING A GAS-LIQUID MIXTURE This invention relates to devices for dispensing gas-liquid mixtures. mainly steam-water mixtures, through the tubes of uniflow steam generators.

Widely known in the art are devices for dispensing steamwater mixtures through the tubes of uniflow steam generators wherein the mixture delivered into the header is dispensed through the discharge pipes. The steam-water mixture enters the header at a considerable speed which contributes to its efflcient mixing and uniform dispensing through discharge pipes.

These headers can be used within a very limited range of steam content variations, since wide fluctuations of the steam content interfere with the homogeneity of the steam-water mixture which fact, in turn, precludes its uniform dispensing through the discharge pipes of the header.

An object of the present invention resides in providing a device for dispensing gas-liquid mixtures, mainly steam-water mixtures, which will ensure uniform dispensing of the steamwater mixture through the discharge pipes within a wide range of stem content variations.

In conformity with this object a device is proposed for dispensing gas-liquid mixtures, mainly steam-water mixtures, through the pipes of a steam generator whose header has inlet connections and discharge pipes. According to the invention the header incorporates perforated tubes extending throughout the header, one end of each tube communicating with the discharge pipe, and the other end being open. To provide for the separation of the gas-liquid mixture in the header, the number of inlet connections is selected so as make the speed of the gas-liquid mixture flowing along the header axis lower than the critical filrn separation velocity.

It is preferred that the open ends of the tubes have teeth whose tips rest on the header wall.

Given below is a detailed description of the invention with reference to the appended drawings, in which:

FIG. I is an elevation view of the dispenser for a steamwater mixture, according to the invention;

FIG. 2 is a section taken on line II-Il in FIG. 1;

FIG. 3 is a section taken on line III-III in FIG. 1; and

FIG. 4 is a developed view of the perforated tube used in the steam-water mixture dispenser.

A header 1 (FIG. 1) has inlet connections 2 and discharge pipes 3.

The number of inlet connections is selected so as to make the maximum speed of the steam-water mixture flowing axially through the header 1 lower than the critical liquid film separation velocity.

The axial speed of the steam-water mixture along the header provides for efficient separation of the mixture inside the header proper so that the steam-water mixture is separated into steam and water. The steam will be in the upper portion of the header 1 and the water in the lower portion thereof. To insure favorable conditions of dispensing the mixture, end 4 (FIG. 2) of the inlet connection 2 is blind and tapered, while its lower portion has holes 5 for the discharge of the steamwater mixture.

Installed inside the header 1 in each discharge pipe 3 is a tube 6 perforated along its entire length (FIG. 3). One end of the tube 6 communicates with the discharge pipe 3 while the other end is open. The open end has teeth 8 whose tips rest on the walls of the header 1. Water enters the tube 6 between these teeth. I

Holes 7 of the tube 6 are arranged along a helix as shown in the developed view of the tube 6 in FIG. 4. To insure gradual changes of the water level in the header at a low steam content, the diameter of the holes in the upper portion of the tube 6 is made smaller than those in the lower portion.

The total area of the holes 7 in the tube 6 is calculated to accept the maximum possible discharge rate of the steam-water mixture, the water level in the header 1 being at the lowest mark, i.e. just a little higher than the height of the teeth 8.

The steam-water mixture dispenser functions as follows.

The steam-water mixture enters the header 1 through the inlet connections 2 and holes 5 located in the lower portion of said connections. From each connection 2 the steam-water mixture flows in two directions along the axis of the header 1 at a speed required for the separation of steam. The steam rises to the upper portion of the header I while the water is accumulated in its lower portion. Thus the upper and lower portions of the header will be filled with steam and water. respectively. Then the steam will flow from the upper portion of the header into the tube 6 through the upper nonflooded holes 7.

The number of the open holes 7 through which the steam flows into the tube 6 depends upon the height of the water level in the header 1. The steam flowing out from the upper portion of the header 1 through the nonflooded holes 7 is throttled, whereby a certain rarefaction is created in the upper portion of the tube 6 as compared with the pressure in the upper steam-filled portion of the header.

Due to the rarefaction therein the tube 6, the water level in will be higher than that in the header 1. If the rarefaction is insufficient to make the water in the tube 6 rise to the nearest nonflooded row of the holes 7 and become mixed with the steam, the water will start accumulating in the header and the water level will keep rising until it reaches the nearest hole in the tube through which the steam flows out. The major portion of water flows from the header I into the tube 6 between the teeth 8 in the tube 6 while the smaller portion of the water flows through the flooded holes 7 of the tube 6.

Thus, the water level in the header 1 settles such that the water level in the tube 6 reaches the nonflooded hole 7 where the steam and water will be mixed, that is, the process of selfregulation will take place in the device.

To illustrate the process of self-regulation, let us consider a few examples of changes in the operating conditions.

The weight rate of the steam-water mixture entering the header remains constant, but:

a. The steam content in the mixture has increased.

An increase of the steam content at a constant rate of mixture flow will lead to an increased consumption of steam and a corresponding reduction of water consumption.

The increased rate of flow through the nonflooded holes 7 will raise the pressure difference in them and, consequently, it will increase the amount of liquid entering the tube 6 from the header I which will bring about a drop of water level in the header. The water level will also drop in the header I due to a reduction in the moisture content of the steam entering the header through the inlet connections 2. This drop of water level in the header 1 will, in turn, increase the required rarefaction for raising the water to greater height than it has been at the previous condition so that a new steady water level settles, corresponding to the new higher steam content.

b. The steam content in the mixture is decreased.

A decrease in the steam content at a constant rate of mixture flow will bring about a reduction of steam consumption and a corresponding increase in water consumption.

The reduction of steam consumption through the nonflooded holes will reduce the pressure difference therein thus diminishing the amount of liquid flowing from the header 1 into the tubes 6 which will raise the water level in the header 1.

The water level in the header 1 will rise also due to increased moisture content in the steam flowing in through the inlet connections 2.

The increased water level in the header 1 will, in turn, reduce the rarefaction required for raising the liquid to a smaller height than at the previous condition. As a result, a new steady water level will settle in the header, corresponding to the new lower steam content.

The steam-water mixture dispenser manufactured in conformity with the present invention has undergone experimental checks under various pressures and within a wide range of steam content variation.

In particular, at atm and a steam content x varying from 0.15 to 0.85, the deviations of the steam content from a mean value in individual tubes have been AX x X m X= 0.02 0.1; a smaller deviation takes place at a steam content x=0.l 0.3 and X= 0.7 0.9. A larger deviation has been registered at a steam content X= 0.4 0.6.

The above-described dispenser can also be utilized for dispensing any other kind of gas-liquid mixture.

We claim:

1. A device for dispensing a gas-liquid mixture comprising: a horizontal header; a plurality of inlet pipe connections for a gas-liquid mixture connected to said header. the number of said connections being selected to provide separation of the gas and liquid in the header; open discharge pipes connected to said header at the top thereof; vertical tubes installed in said header and provided with holes extending over the entire length of the tubes. the upper end of each tube extending-into and being in communication with one of the discharge pipes, and the lower end being open. 1

2. A device, according to claim 1. wherein the lower open ends of the tubes are provided with teeth having tips resting on the header 3. A device according to claim 1 wherein said holes extend in helical fashion along the length of each tube.

4. A device according to claim 3' wherein said holes diminish in size upwardly along the tube. 

2. A device, according to claim 1, wherein the lower open ends of the tubes are provided with teeth having tips resting on the header
 3. A device according to claim 1 wherein said holes extend in helical fashion along the length of each tube.
 4. A device according to claim 3 wherein said holes diminish in size upwardly along the tube. 